Mobile notifier

Has anyone thought of this little feature on your mobile phone?
Most, even primitive, phones have an alarm clock. Set the time and the phone rings at that time.
Many people use their mobile phone as a portable digital notepad, saving drafts of SMS messages they never send, but only read back as reminders to do a certain task. (You can also use it as a permanent storage of useful little texts, such as all the ingredients for chili con carne --very handy if you're in the supermarket and just happen to have forgotten your doorstopper "1001 Delicious Recipes".)
So, why can't alarm clock + notes = reminder system? That is, type in a note, set a (date and) time, and save. At the specified date and time, your GSM not only rings, it also shows you the message. Tadaa!
Maybe my phone is just too cheap, and this is a standard feature on the phones that all the cool kids have.